Equiviscous Temperature or EVT. EVT is expressed as a range, typically a 50 degree (F) range. It fluctuates depending upon the particular asphalt being applied. Kettle temperature therefore varies so to ensure the hot liquid asphalt is the correct temperature at the point of application. So, if a particular asphalt has an EVT of 450 degrees (F) you may see kettle temperatures over 500 degrees (F) depending on the distance from the kettle to point of application, ambient temperatures, etc. However, there is a safety rule of thumb that says kettle temperatures should never exceed 50 degrees (F) within the flashpoint of the asphalt itself. The flashpoint as well as the EVT of the particular asphalt are stated on the packaging of the solid asphalt.

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